Quote:
Originally Posted by armyav8tor
I think I understand what you guys are saying. If the car is understeering and doesn't want to turn-in, take out the steering input and put it back in, repeat until the car submits.
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This is how I would describe it (the diagram was drawn in MS Paint, so don't laugh
And, obviously, the lines drawn aren't ideal and are actually drawn to exaggerate my point).
You are entering a corner and arrive at point (A). And, the speed you are carrying (along with bunch of other factors like amount of tire grip, steering wheel position, etc, etc) is about to cause you to travel along the red line to get to point (B). Then, you have 3 options:
(i) maintain throttle and steering positions and understeer and move along the red line. Then, due to the front tires now pushing, you've lost speed by the time you get to point (B). Or, worse, follow the red line and go off; or,
(ii) reduce the speed and travel along the green line; or,
(iii) while maintaining speed (or, even increasing it a bit), actively jerk the steering wheel to the left and cause the car to go along what is illustrated as green line.
If you opt with (iii), then that initial jerking motion, if left unchecked, most likely will cause the car to oversteer and spin, per purple line. So, after the initial jerk, you immediately steer back and you arrive at point (B) along the green line. From point (B) to (C), repeat. Same for from point (C) to (D).
If you manage the degree of said steering jerks and unwinds, and repeat (hence, "saw"), there are some corners where this works very well, and you can carry higher speed through and not have the car get all upset. In other words, where otherwise you'd be understeering and pushing the front tires and scrubbing off speed, you can, with careful active series of steering inputs, carry speed and not drift off to the outside.
Due to the saw'ing actions, tight quick corners aren't good for this (unless the driver can saw super-rapidly per hyper shifter-go-kart pace
). Nor are long sweeping turns. Medium, slightly-extended turns are perfect because there's time and room for the driver to saw 2 to 3 times to complete the turn. Kind of like man-handling a heavy car that wasn't going to make the corner while carrying certain amount of speed.
You can almost look at this as converting what is analog (i.e. long smooth curve) to discretized digital segments (with each of those digital elemental bars not going outside of the overall curve). On that note, that logic can be applied to driving 'smoothly' (analog) vs lots of steering movements (digital).